MicroRNA-124 (miR-124) is abundantly expressed in neurons in the mammalian central ner-vous system, and plays critical roles in the regulation of gene expression during embryonic neurogenesis and postnatal neural differentiation. However, the expression proifle of miR-124 after spinal cord injury and the underlying regulatory mechanisms are not well understood. In the present study, we examined the expression of miR-124 in mouse brain and spinal cord after spinal cord injury usingin situ hybridization. Furthermore, the expression of miR-124 was examined with quantitative RT-PCR at 1, 3 and 7 days after spinal cord injury. The miR-124 expression in neurons at the site of injury was evaluated by in situ hybridization combined with NeuN immunohistochemical staining. The miR-124 was mainly expressed in neurons through-out the brain and spinal cord. The expression of miR-124 in neurons significantly decreased within 7 days after spinal cord injury. Some of the neurons in the peri-lesion area were NeuN+/miR-124?. Moreover, the neurons distal to the peri-lesion site were NeuN+/miR-124+. These ifndings indicate that miR-124 expression in neurons is reduced after spinal cord injury, and may relfect the severity of spinal cord injury.
作者: 刊期: 2015年第07期
Necroptosis is characterized by programmed necrotic cell death and autophagic activation and might be involved in the death process of dopaminergic neurons in Parkinson’s disease. We hypothesized that necrostatin-1 could block necroptosis and give protection to dopaminergic neurons. There is likely to be crosstalk between necroptosis and other cell death pathways, such as apoptosis and autophagy. PC12 cells were pretreated with necroststin-1 1 hour before expo-sure to 6-hydroxydopamine. We examined cell viability, mitochondrial membrane potential and expression patterns of apoptotic and necroptotic death signaling proteins. The results showed that the autophagy/lysosomal pathway is involved in the 6-hydroxydopamine-induced death pro-cess of PC12 cells. Mitochondrial disability induced overactive autophagy, increased cathepsin B expression, and diminished Bcl-2 expression. Necrostatin-1 within a certain concentration range (5–30 μM) elevated the viability of PC12 cells, stabilized mitochondrial membrane potential, inhibited excessive autophagy, reduced the expression of LC3-II and cathepsin B, and increased Bcl-2 expression. These findings suggest that necrostatin-1 exerted a protective effect against injury on dopaminergic neurons. Necrostatin-1 interacts with the apoptosis signaling pathway during this process. This pathway could be a new neuroprotective and therapeutic target in Par-kinson’s disease.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
Both neurons and glia throughout the central nervous system are organized into networks by gap junctions. Among glia, gap junctions facilitate metabolic homeostasis and intercellular communication. Among neurons, gap junctions form electrical synapses that function pri-marily for communication. However, in neurodegenerative states due to disease or injury gap junctions may be detrimental to survival. Electrical synapses may facilitate hyperactivity and bystander killing among neurons, while gap junction hemichannels in glia may facilitate in-lfammatory signaling and scar formation. Advances in understanding mechanisms of plasticity of electrical synapses and development of molecular therapeutics to target glial gap junctions and hemichannels offer new hope to pharmacologically limit neuronal degeneration and en-hance recovery.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
Deep brain stimulation has become a well-established symptomatic treatment for Parkinson’s disease during the last 25 years. Besides improving motor symptoms and long-term motor com-plications, positive effects on patients’ mobility, activities of daily living, emotional well-being and health-related quality of life have been recognized. Apart from that, numerous clinical trials analyzed effects on non-motor symptoms and side effects of deep brain stimulation. Several technical issues and stimulation paradigms have been and are still being developed to optimize the therapeutic effects, minimize the side effects and facilitate handling. This review summarizes current therapeutic issues,i.e., patient and target selection, surgical procedure and programming paradigms. In addition it focuses on neuropsychological effects and side effects of deep brain stimulation.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
Both genetic and environmental factors are important in the pathogenesis of Parkinson’s disease. Asα-synuclein is a major constituent of Lewy bodies, a pathologic hallmark of Parkinson’s dis-ease, genetic aspects ofα-synuclein is widely studied. However, the inlfuence of dietary factors such as quercetin onα-synuclein was rarely studied. Herein we aimed to study the neuropro-tective role of quercetin against various toxins affecting apoptosis, autophagy and aggresome, and the role of quercetin onα-synuclein expression. PC12 cells were pre-treated with quercetin (100, 500, 1,000 μM) and then together with various drugs such as 1-methyl-4-phenylpyridin-ium (MPP+; a free radical generator), 6-hydroxydopamine (6-OHDA; a free radical generator), ammonium chloride (an autophagy inhibitor), and nocodazole (an aggresome inhibitor). Cell viability was determined using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltertazolium bromide (MTT) assay. Apoptosis was detected by annexin V-lfuorescein isothiocyanate and propidium iodide through the use of lfuorescence activated cell sorter.α-Synuclein expression was detected by western blot assay and immunohistochemistry. The role of α-synuclein was further studied by knocking outα-synuclein using RNA interference. Cell viability increased at lower concen-trations (100 and 500 μM) of quercetin but decreased at higher concentration (1,000 μM). Quercetin exerted neuroprotective effect against MPP+, ammonium chloride and nocodazole at 100 μM. MPP+ induced apoptosis was decreased by 100 μM quercetin. Quercetin treatment in-creasedα-synuclein expression. However, knocking outα-synuclein exerted no signiifcant effect on cell survival. In conclusion, quercetin is neuroprotective against toxic agentsvia affecting var-ious mechanisms such as apoptosis, autophagy and aggresome. Becauseα-synuclein expression is increased by quercetin, the role of quercetin as an environmental factor in Parkinson’s disease pathogenesis needs further investigation.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
Electroacupuncture has therapeutic effects on ischemic brain injury, but its mechanism is still poorly understood. In this study, mice were stimulated by electroacupuncture at theBaihui (GV20) acupoint for 30 minutes at 1 mA and 2/15 Hz for 5 consecutive days. A cerebral isch-emia model was established by ligating the bilateral common carotid artery for 15 minutes. At 72 hours after injury, neuronal injury in the mouse hippocampus had lessened, and the number of terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-positive cells reduced after electroacupuncture treatment. Moreover, expression of adenosine monophos-phate-activated protein kinaseα (AMPKα) and phosphorylated AMPKα was up-regulated. Intraperitoneal injection of the AMPK antagonist, compound C, suppressed this phenomenon. Our ifndings suggest that electroacupuncture preconditioning alleviates ischemic brain injury via AMPK activation.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
In this study, we aimed to determine gastrointestinal problems associated with neurogenic bowel dysfunction in spinal cord injury patients and to assess the efifcacy of bowel program on gas-trointestinal problems and the severity of neurogenic bowel dysfunction. Fifty-ifve spinal cord injury patients were included in this study. A bowel program according to the characteristics of neurogenic bowel dysfunction was performed for each patient. Before and after bowel program, gastrointestinal problems (constipation, dififcult intestinal evacuation, incontinence, abdominal pain, abdominal distension, loss of appetite, hemorrhoids, rectal bleeding and gastrointestinal induced autonomic dysrelfexia) and bowel evacuation methods (digital stimulation, oral med-ication, suppositories, abdominal massage, Valsalva maneuver and manual evacuation) were determined. Neurogenic bowel dysfunction score was used to assess the severity of neurogenic bowel dysfunction. At least one gastrointestinal problem was identiifed in 44 (80%) of the 55 patients before bowel program. Constipation (56%, 31/55) and incontinence (42%, 23/55) were the most common gastrointestinal problems. Digital rectal stimulation was the most common method for bowel evacuation, both before (76%, 42/55) and after (73%, 40/55) bowel program. Oral medication, enema and manual evacuation application rates were signiifcantly decreased and constipation, dififcult intestinal evacuation, abdominal distention, and abdominal pain rates were signiifcantly reduced after bowel program. In addition, mean neurogenic bowel dysfunction score was decreased after bowel program. An effective bowel program decreases the severity of neurogenic bowel dysfunction and reduces associated gastrointestinal problems in patients with spinal cord injury.
作者: 刊期: 2015年第07期
Although ultrasound measurements have been used in previous studies on carpal tunnel syn-drome to visualize injury to the median nerve, whether such ultrasound data can indicate the severity of carpal tunnel syndrome remains controversial. The cross-sectional areas of the median nerve at the tunnel inlet and outlet can show swelling and compression of the nerve at the carpal. We hypothesized that the ratio of the cross-sectional areas of the median nerve at the carpal tunnel inlet to outlet accurately relfects the severity of carpal tunnel syndrome. To test this, high-resolution ultrasound with a linear array transducer at 5–17 MHz was used to assess 77 pa-tients with carpal tunnel syndrome. The results showed that the cut-off point for the inlet-to-outlet ratio was 1.14. Signiifcant differences in the inlet-to-outlet ratio were found among patients with mild, moderate, and severe carpal tunnel syndrome. The cut-off point in the ratio of cross-section-al areas of the median nerve was 1.29 between mild and more severe (moderate and severe) carpal tunnel syndrome patients with 64.7% sensitivity and 72.7% speciifcity. The cut-off point in the ratio of cross-sectional areas of the median nerve was 1.52 between the moderate and severe carpal tunnel syndrome patients with 80.0% sensitivity and 64.7% speciifcity. These results suggest that the inlet-to-outlet ratio relfected the severity of carpal tunnel syndrome.
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期
作者: 刊期: 2015年第07期